import { getCellValueByColumnName } from "./sheetUtils"
import { Product } from "./Product"
import { Shop } from "./shopifyApi"

// --- Constants ---
const BATCH_INTERVAL_MS = 30 * 1000 // 30 seconds
const LOCK_TIMEOUT_MS = 10 * 1000 // 10 seconds for lock acquisition
const CACHE_KEY_EDITS = "pendingEdits"
const CACHE_KEY_LAST_EDIT_TIME = "lastEditTime"
const SCRIPT_PROPERTY_TRIGGER_SCHEDULED = "batchTriggerScheduled"

export function onEditQueue(e) {
  const sheet = e.source.getActiveSheet()
  if (sheet.getName() !== "product_inventory") {
    console.log("skipping edit on sheet " + sheet.getName())
    return
  }
  const range = e.range
  const row = range.getRow()
  const sku = getCellValueByColumnName(sheet, "sku", row)
  if (!sku) {
    console.log("No SKU found for row " + row)
    return
  }
  // Make sure SKU conforms to expected patterns
  if (sku.match(`\\?`) || sku.match(`n$`)) {
    console.log("SKU is a placeholder ('?' or 'n...'), skipping batching.")
    return
  }
  // Acquire a user lock to prevent multiple onEdit calls from clashing
  const documentLock = LockService.getDocumentLock()
  try {
    documentLock.waitLock(LOCK_TIMEOUT_MS)

    const scriptProperties = PropertiesService.getScriptProperties() // Shared cache for all users

    // 1. Accumulate edits in cache
    let pendingEdits = []
    try {
      pendingEdits = JSON.parse(
        scriptProperties.getProperty(CACHE_KEY_EDITS) || "[]"
      )
    } catch (e) {
      console.log("Cache corruption: " + e.message)
      scriptProperties.setProperty(CACHE_KEY_EDITS, "[]")
    }
    const existingIndex = pendingEdits.findIndex((item) => item.sku === sku)
    if (existingIndex !== -1) {
      console.log("New edit on queued SKU '"+sku+"', resetting timer...")
      pendingEdits[existingIndex].timestamp = Date.now()
    } else {
      console.log("New SKU '"+sku+"' added to queue.")
      pendingEdits.push({ sku, timestamp: Date.now() })
    }
    scriptProperties.setProperty(CACHE_KEY_EDITS, JSON.stringify(pendingEdits))
  } catch (error) {
    console.log(
      "Error in onEdit (lock acquisition or cache operation): " + error.message
    )
  } finally {
    documentLock.releaseLock()
  }
}

export function processBatchedEdits() {
  const scriptLock = LockService.getScriptLock() // Use script lock for the processing function
  try {
    scriptLock.waitLock(LOCK_TIMEOUT_MS)

    const scriptProperties = PropertiesService.getScriptProperties()

    let pendingEdits = []
    try {
      const pendingEditsStr = scriptProperties.getProperty(CACHE_KEY_EDITS)
      pendingEdits = pendingEditsStr ? JSON.parse(pendingEditsStr) : []
    } catch (e) {
      console.log("Cache corruption: " + e.message)
      scriptProperties.setProperty(CACHE_KEY_EDITS, "[]")
    }

    console.log(`Total SKUs in queue: ${pendingEdits.length}`)
    const now = Date.now()
    const toProcess = pendingEdits.filter(
      (edit) => now - edit.timestamp > BATCH_INTERVAL_MS
    )
    if (toProcess.length > 0) {
      let shop = new Shop()
      console.log(`Processing ${toProcess.length} SKUs...`)
      toProcess.forEach((edit) => {
        console.log(
          `Processing SKU ${edit.sku}, Timestamp: ${new Date(edit.timestamp)}`
        )
        // Make sure SKU conforms to expected patterns
        if (!edit.sku.match(/^\w+-\d{4}$/)) {
          console.log(`SKU ${edit.sku} is not valid, skipping processing.`)
          return
        }
        let p = new Product(edit.sku)
        p.UpdateShopifyProduct(shop)
      })

      pendingEdits = pendingEdits.filter(
        edit => !toProcess.some(p => p.sku === edit.sku)
      );
      scriptProperties.setProperty(CACHE_KEY_EDITS, JSON.stringify(pendingEdits));

      console.log(`Processed ${toProcess.length} edits.`)
    } else {
      console.log("No pending edits to process.")
    }
  } catch (error) {
    console.log(
      "Error in processBatchedEdits (lock acquisition or processing): " +
        error.message
    )
  } finally {
    scriptLock.releaseLock()
  }
}